Trafficking of gold nanorods in breast cancer cells: uptake, lysosome maturation, and elimination

Probing the relevance of 3D cancer models in nanomedicine research

For decades, 2D cell culture format on plastic has been the main workhorse in cancer research. Though many important understandings of cancer cell biology were derived using this platform, it is not a fair representation of the in vivo scenario. In this review, both established and new 3D cell culture systems are discussed with specific references to anti-cancer drug and nanomedicine applications. 3D culture systems exploit more realistic spatial, biochemical and cellular heterogeneity parameters to bridge the experimental gap between in vivo and in vitro settings when studying the performance and efficacy of novel nanomedicine strategies to manage cancer. However, the complexities associated with 3D culture systems also necessitate greater technical expertise in handling and characterizing in order to arrive at meaningful experimental conclusions. Finally, we have also provided future perspectives where cutting edge 3D culture technologies may be combined with under-explored technologies to build better in vitro cancer platforms.

Two orders of magnitude fluorescence enhancement of aluminum phthalocyanines by gold nanocubes: a remarkable improvement for cancer cell imaging and detection

The metal-enhanced fluorescence (MEF) by metal nanoparticles is a useful technique for fluorescence detections in biological systems. The MEF effects with gold nanorods (AuNRs) and nanocubes (AuNCs) for fluorescence enhancements of sulfonated aluminum phthalocyanine (AlPcS), a commonly used and clinical approved photosensitizer for photodynamic therapy of cancers, were studied in this work. For the AuNRs which have the low aspect ratios with the corresponding longitudinal surface plasma resonance (LSPR) band in the region of 600-750 nm, the fluorescence quenching of conjugated AlPcS was found. Whereas for the AuNRs that have the LSPR bands of 800-900 nm, the MEF of AlPcS was obtained with the enhancing factor of 2-6 times, respectively. Using AuNCs, a great enhancement of AlPcS fluorescence was achieved with an enhancing factor of 150 times. Using two cancer cell lines as in vitro models, an outstanding fluorescence enhancement of AlPcS-AuNCs conjugates in cells, relative to AlPcS alone, was obtained under one-photon excitation (OPE) of 405 nm. Moreover, the bright fluorescence image of AlPcS-AuNCs in cells was also achieved under the two-photon excitation (TPE) of an 800 nm femtosecond laser. The high-quality cell imaging with either OPE or TPE demonstrated the potential of AlPcS-AuNCs in cancer cell detections.

Gold nanoparticles in breast cancer treatment: promise and potential pitfalls

Despite remarkable achievements in the treatment of breast cancer, some obstacles still remain. Gold nanoparticles may prove valuable in addressing these problems owing to their unique characteristics, including their enhanced permeability and retention in tumor tissue, their light absorbance and surface plasmon resonance in near-infrared light, their interaction with radiation to generate secondary electrons, and their ability to be conjugated with drugs or other agents. Herein, we discuss some basic concepts of gold nanoparticles, and early results from studies regarding their use in breast cancer, including toxicity and side effects. We also discuss these particles' potential clinical applications.